There are still so many puzzles that I haven't tried yet -- Distress Signal is a good one. I read that Rene had used timers, and that Werbad had a solution, but thank goodness for spoiler tags so I could meet that puzzle head-on with a good, long blank stare, until a solution occurred to me: I had the same general idea as Werbad, except that I encode the values as four two-bit nibbles. A simple lookup table gives two barrels for each solution crate. The top two bits identifies which of the four barrels, and the bottom two bits carry the nibble which are recombined on the other side.

That is a really classic, fun puzzle. It's simple, there are not a lot of moving parts, and there is a lot of space to work in. And there is an interesting, difficult puzzle to figure out before you can even start building the machinery.

On my design: I spent a lot of time working out an approach, and then simplified as much as possible. I like to try for the austere aesthetic, although I've written my share of crazy mechanical "clockworks". I also like these slow mesmerizing lines of barrels, and solutions that seem to flow like water.

The details: If you pour the sequence n .. 0, then F .. n + 1 (where n is the solution crate), making the 16-barrel sequence from n down to zero and wrapping back to F and then to n + 1, you'll notice that the barrels split in three ways:

1. First left, then right (L R) if the nose barrel matches the solution2. First left, then right, then left (L R L)3. First right, then left, then right (R L R)

I added an initial zero, so that the three sequences are (L R), (L R L), or (L R L R) and in that third case, the L is just the single zero barrel, and the R L R is a complete set of 16 barrels.

Now, if you drop the first L in each case, then in case 1 the R gives the number of F's to add to F, in case 2 the R + L gives the number, and in the third case, the last R gives the number. I discard the first sequence of L (left flowing barrels), then keep the rest, and if there is a *second* stream of R (case 3), then since R + L + R gives 16 barrels, I simply double the second set of R to get the correct number of F's to add to F.

Very nice solution! Makes mine seem clumsy and inefficient: nosimatI used a different approach, which turned out much slower than yours.

In fact, seeing that solution gave me an idea for a solution that might work works for: The Van: xuxerup

Edit:Got an idea for a general solution that, given enough space, should solve with about the same speed for any vehicle length of 3 crates and above.So while I'm at it, might just as well do this:The Bus: kuvebit